What a pickle-a metagenomic perspective on the cucumber fermentation

Area of Science:

• Microbiology
• Food Science
• Metagenomics

Background:

• Food fermentation involves complex microbial interactions, challenging traditional analysis.
• Understanding these dynamics is crucial for optimizing fermentation processes and product quality.

Purpose of the Study:

• To investigate the microbial dynamics during spontaneous cucumber fermentation.
• To identify key microbial players and their roles in fermentation, particularly comparing organic and commercial cucumbers.
• To explore the influence of phages on microbial community structure.

Main Methods:

• Utilized nanopore sequencing for metagenomic analysis of cucumber fermentation over 90 days.
• Analyzed samples from both organic and commercial cucumber cultivation.
• Focused on identifying bacterial strains, including coagulase-negative cocci and lactic acid bacteria.

Main Results:

• First report of coagulase-negative cocci (Staphylococcus saprophyticus, Staphylococcus schleiferi) in cucumber fermentation.
• Organic cucumbers showed lower incidence and diversity of phages compared to commercial ones.
• Lactic acid bacteria dominance was observed even without significant phage presence, challenging existing hypotheses.

Conclusions:

• Cucumber fermentation involves a diverse microbiome, with specific bacteria identified for the first time.
• Phage presence may be lower in organic cucumber fermentation, with implications for microbial ecology.
• Metagenomics offers a powerful tool for understanding fermentation microbiome complexity and product maturity's role.